Charging method, battery management system, battery, and charging device

Abstract

A charging method may include: sending a first command to a charging device, the first command being used to control the charging device to output an oscillation current to the battery during a first time period in a charging process, where the oscillation current may include n cycle periods, n being a positive integer greater than 1, each of the cycle periods may include a first sub-period and a second sub-period, a current output by the charging device during the first sub-period is a first current, a current output by the charging device during the second sub-period is a second current, and a direction of the first current may be opposite to that of the second current; and sending a second command to the charging device, the second command being used to instruct the charging device to charge the battery during a second time period in the charging process.

1 . A charging method, applied to a battery management module of a battery and comprising:
 sending a first command to a charging device, the first command being used to control the charging device to output an oscillation current to the battery during a first time period in a charging process, wherein the oscillation current comprises n cycle periods, n being a positive integer greater than 1, each of the cycle periods comprises a first sub-period and a second sub-period, a current output by the charging device during the first sub-period is a first current, a current output by the charging device during the second sub-period is a second current, and a direction of the first current is opposite to that of the second current; and   sending a second command to the charging device, the second command being used to instruct the charging device to charge the battery during a second time period in the charging process.   
     
     
         2 . The charging method according to  claim 1 , characterized in that the charging process comprises at least one first time period and at least one second time period. 
     
     
         3 . The charging method according to  claim 1 , characterized in that the first current is a charging current of the battery, the second current is a discharging current of the battery, and a quantity of electricity charged with the first current during the first sub-period is less than or equal to a quantity of electricity discharged with the second current during the second sub-period. 
     
     
         4 . The charging method according to  claim 3 , characterized in that a duration of the first sub-period is shorter than or equal to a duration of the second sub-period. 
     
     
         5 . The charging method according to  claim 1 , characterized in that the method further comprises:
 receiving a maximum output frequency of the charging device sent by the charging device; and   determining a duration of the cycle period based on the maximum output frequency.   
     
     
         6 . The charging method according to  claim 1 , characterized in that the first sub-period and/or the second sub-period is 2 ms. 
     
     
         7 . The charging method according to  claim 1 , characterized in that a number n of the cycle periods is 10000. 
     
     
         8 . The charging method according to  claim 1 , characterized in that the method further comprises:
 obtaining a state of charge SOC and a state of health SOH of the battery; and   determining a maximum magnitude of the first current and/or the second current based on the SOC and the SOH.   
     
     
         9 . The charging method according to  claim 8 , characterized in that the first command comprises a maximum magnitude of the first current and/or the second current. 
     
     
         10 . The charging method according to  claim 1 , characterized in that the sending a first command to a charging device comprises:
 sending the first command to the charging device when the battery is connected to the charging device.   
     
     
         11 . The charging method according to  claim 1 , characterized in that the sending a first command to a charging device comprises:
 sending the first command to the charging device when it is determined that the battery meets at least one of the following conditions:   a temperature of the battery is less than or equal to a first threshold;   the battery is being charged in fast charging mode, the fast charging mode being a charging mode with a charging speed greater than or equal to a second threshold;   the battery has completed x cycles of charging and discharging, x being a positive integer;   the battery has lost y % of its capacity, y being a positive number; and   the battery has been in service for z days, z being a positive integer.   
     
     
         12 . A charging method, applied to a charging device and comprising:
 receiving a first command sent by a battery management module of a battery;   outputting an oscillation current to the battery during a first time period in a charging process according to the first command, wherein the oscillation current comprises n cycle periods, n being a positive integer greater than 1, each of the cycle periods comprises a first sub-period and a second sub-period, a current output during the first sub-period is a first current, a current output during the second sub-period is a second current, and a direction of the first current is opposite to that of the second current;   receiving a second command sent by the battery management module; and   charging the battery during a second time period in the charging process according to the second command.   
     
     
         13 . The charging method according to  claim 12 , characterized in that the charging process comprises at least one first time period and at least one second time period. 
     
     
         14 . The charging method according to  claim 12 , characterized in that the first current is a charging current of the battery, the second current is a discharging current of the battery, and a quantity of electricity charged with the first current during the first sub-period is less than or equal to a quantity of electricity discharged with the second current during the second sub-period. 
     
     
         15 . The charging method according to  claim 12 , characterized in that a duration of the first sub-period is shorter than or equal to a duration of the second sub-period. 
     
     
         16 . The charging method according to  claim 12 , characterized in that the method further comprises:
 sending a maximum output frequency of the charging device to the battery management module, the maximum output frequency being used to determine a duration of the cycle period.   
     
     
         17 . The charging method according to  claim 16 , characterized in that the first sub-period and/or the second sub-period is 2 ms. 
     
     
         18 . The charging method according to  claim 12 , characterized in that a number n of the cycle periods is 10000. 
     
     
         19 . The charging method according to  claim 12 , characterized in that the first command comprises a maximum magnitude of the first current and/or the second current, the maximum magnitude of the first current and/or the second current being determined based on a state of charge SOC and a state of health SOH of the battery. 
     
     
         20 . The charging method according to  claim 12 , characterized in that the receiving a first command sent by a battery management module of a battery comprises:
 receiving the first command sent by the battery management module of the battery when the battery is connected to the charging device.